A method for sub-micrometer N(-)collector layer fabricated by Ultra-High Vacuum Chemical Vapor Deposition i-Si epitaxy and ion implantation doping is presented in this paper. The characteristics of this sub-micrometer N(-)collector layer are investigated. The Spreading Resistance Probe figures show that the transition region of the N(-)collector dopant profile is steep and the measure by an Atomic Force Mcroscope shows that the surface roughness is strongly related to the growth condition of the i-Si. The rocking curve by X-Ray Diffraction and the performance of SiGe Heterojunction Bipolar Transistor device demonstrate the good quality of the SiGe layer grown on this kind of N(-)collector layer. The BV(cbo) of the SiGeHBT with this sub-micrometer N-collector is 23.5V high, and the f(T) is 11 GHz.

Keywords: UHV/CVD; Si epitaxy; ion implantation; SiGe; HBT